'Star' labelling mandatory for passenger cars from April 2013

Washington, Apr 23: Air pollution over northern India has plummeted to a 20-year-low for this time of the year, according to satellite data published by US space agency National Aeronautics and Space Administration (NASA).
The US space agency's satellite sensors observed aerosol levels at a 20-year low post the countrywide lockdown, implemented to slow the spread of the novel coronavirus.

"We knew we would see changes in atmospheric composition in many places during the lockdown," said Pawan Gupta, a Universities Space Research Association (USRA) scientist at NASA''s Marshall Space Flight Center. "But I have never seen aerosol values so low in the Indo-Gangetic Plain at this time of year," added Mr Gupta.

Acting Assistant Secretary of State for South and Central Asia Alice G Wells tweeted, "These images from NASA were taken each spring starting in 2016 and show a 20-year low in airborne particle levels over India. When India and the world are ready to work and travel again, let's not forget that collaborative action can result in cleaner air."

The data published with maps show aerosol optical depth (AOD) in 2020 compared to the average for 2016-2019. Aerosol optical depth is a measure of how light is absorbed or reflected by airborne particles as it travels through the atmosphere.

If aerosols are concentrated near the surface, an optical depth of 1 or above indicates very hazy conditions. An optical depth, or thickness, of less than 0.1 over the entire atmospheric vertical column is considered "clean." The data were retrieved by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite.

In the first few days of the lockdown, it was difficult to observe a change in the pollution signature. "We saw an aerosol decrease in the first week of the shutdown, but that was due to a combination of rain and the lockdown," said Mr Gupta.

Around March 27, heavy rain poured over vast areas of northern India and helped clear the air of aerosols. Aerosol concentrations usually increase again after such heavy precipitation.

"After the rainfall, I was really impressed that aerosol levels did not go up and return to normal. We saw a gradual decrease and things have been staying at the level we might expect without anthropogenic emissions," Mr Gupta said.

On March 25, the Indian government placed its 1.3 billion citizens under a strict lockdown to reduce the spread of COVID-19. The countrywide mandate decreased activity at factories and severely reduced car, bus, truck and airplane traffic. Every year, aerosols from anthropogenic (human-made) sources contribute to unhealthy levels of air pollution in many Indian cities.

Aerosols are tiny solid and liquid particles suspended in the air that reduce visibility and can damage the human lungs and heart.

In southern India though, the story is a little hazier. Satellite data show aerosol levels have not yet decreased to the same extent. In fact, levels seem to be slightly higher than in the past four years. The reasons are unclear but could be related to recent weather patterns, agricultural fires, winds or other factors.

"This a model scientific experiment," Robert Levy, program leader for NASA's MODIS aerosol products, said about the lockdown and its effects on pollution.

"We have a unique opportunity to learn how the atmosphere reacts to sharp and sudden reductions in emissions from certain sectors. This can help us separate how natural and human sources of aerosols affect the atmosphere," Mr Levy added.

New Delhi, Jan 1: The new Army chief Lieutenant General MM Naravane on Wednesday said that India needs to pay more attention to its border along China and asserted that the force is capable of dealing with any security challenge.

"We have been giving attention to our western front in the past. The northern front now also requires an equal amount of attention... The Army is capable of tackling any dangers to the country," General Naravane told reporters after receiving the first Guard of Honour as the Army chief.

"In that context, we are now going in for capability development and enhancement of our capacities even in our northern borders which includes the northeastern part of our country," he said.

On the border dispute with China, the Army chief said that continuing peace along the border will pave the way for a solution.

He said: "We have been able to maintain peace and tranquility along borders and I'm sure that situation will prevail. By maintaining this, we will be able to set the stage for the eventual solution."

General Naravane said that operational readiness and modernisation will be among the top priorities of the Army under his leadership.

"Our priority will be to be ready to meet any challenge and to be operationally prepared at all times. This will happen as a result of modernisation. We will continue to build our capability especially in the North and Northeast region of our country," he said.

He said that the Indian Army will pay special attention to respect human rights. "We will also pay special emphasis on raising security awareness among ranks and file and pay special attention to respect human rights," the Army chief said.

Assuring the country on security, he said, "All three services — the Army, the Navy and the Air Force — are ready to defend the country."

He extended wishes to people in the new year and hoped that the country will make huge progress in this decade.

General Naravane took over as the 28th Chief of the Army Staff (COAS) on Tuesday, succeeding General Bipin Rawat who has become India's first Chief of Defence Staff (CDS).

General Naravane was previously the Vice Chief of Army Staff.